The low bid for constructing the Carpenter Street underpass, the first phase in the massive Springfield rail-consolidation project, came in below estimates.

The apparent low bidder, local firm Halverson Construction Co., submitted a $10,189,034 bid to construct the underpass, which was “about 10 percent under our estimate,” said Jim Moll of the Springfield engineering and planning firm Hanson Professional Services that is overseeing design, engineering and project management for the rail consolidation.

The long-term Springfield Rails Improvement Project, which is being carried out in phases, will consolidate freight and passenger rail traffic to the 10th Street corridor. The Carpenter Street underpass component will bypass the Norfolk Southern Corp. track between Ninth and 11th streets, which is expected to increase access to Springfield’s medical facilities and cut back on delays for emergency vehicles.

Halverson’s roughly $10.2 million bid was the lowest of four submitted. The bids were opened June 13.

The current hope is for construction to get under way in late August or early September, which will likely extend through 2015 and possibly into 2016, Moll said.

Carpenter Street between Ninth and 11th streets will be closed during construction, Moll said.

The overall rail-consolidation project is expected to cost $315 million, and is being partially funded by a Transportation Investment Generating Economic Recovery grant from the U.S. Department of Transportation and through the Illinois Commerce Commission’s Grade Crossing Protection Fund.

City officials are working with U.S. Sen. Dick Durbin, D-Ill., and other members of the Illinois congressional delegation to garner additional federal funding for the project.

Current estimates put the number of trains traveling through Springfield daily in 2030 at 81, a rather dramatic increase over the next 16 years that would undoubtedly create delays for motor vehicles traveling across the city if much of the rail traffic was still traveling on the Third Street rail corridor, Mayor Mike Houston said last week.